Electric motors are widely used to drive fans in ventilation systems. Typically, such motors are alternating current (AC) motors having a rotor, a stator, and permanent magnets angularly displaced around the rotor. The stator has windings carrying current and positioned to intercept the magnetic field of said permanent magnets during rotation of the motor. Terminals are attached to the electric motor in order to supply the windings with an alternating voltage for energizing the winding and determining the speed of rotation of the rotor.
Ventilations systems are increasingly used in electronic multimedia systems, which are often incorporated into a dashboard of a vehicle. These electronic systems typically include different electronic modules, such as, a radio module, an audio module, a telecommunication module, and/or a navigation module. All of these different modules are often mounted in a limited space behind the dashboard, so that these modules operate while positioned close to one another. These electronic modules tend to generate heat, which can adversely affect their operation. As a consequence, the ventilation systems are added in order to cool the different electronic modules.
As noted above, the space in the electronic systems is limited. In addition, electric motors typically require a winding for driving the motor and a winding for detecting the relative position of the magnetic poles relative to pole pieces provided next to the winding. Each winding takes space and requires a pair of terminals, thus further crowding and adding to the cost of manufacturing the system. Accordingly, a need exists for a ventilation system that may be efficiently used in electronic systems having limited space.